Vacuum mold shuttle system for a glass sheet forming system

ABSTRACT

A vacuum mold shuttle system in a glass sheet forming system includes a vacuum mold mounted on a support frame. A shuttle frame including a pair of generally parallel elongate beams for receiving and supporting the mold support frame thereon. A vacuum source is mounted on the shuttle frame near the end of the beams opposite to the end supporting the mold, a conduit and coupling port for releasably connecting the mold to the vacuum source. At least one guide element is mounted on the support surface of one of the beams for receiving and fixing the position of the mold support frame relative to the shuttle frame to align and prevent movement of the mold support frame with respect to the shuttle frame in any direction as the mold support frame is supported thereon.

CROSS-REFERENCE TO RELATED APPLICATION

This application is the U.S. national phase of PCT Application No.PCT/US2016/060090 filed on Nov. 2, 2016, which claims the benefit ofU.S. provisional Application No. 62/249,567, filed on Nov. 2, 2015, thedisclosures of which are incorporated in their entirety by referenceherein.

TECHNICAL FIELD

This invention relates to a vacuum mold shuttle system and method forforming and transporting a hot glass sheet in a glass sheet bendingsystem.

BACKGROUND

Prior shuttle apparatuses for moving molds in multi-stage glass sheetforming systems are disclosed in U.S. Pat. No. 5,900,034, Mumford etal.; U.S. Pat. No. 5,906,668 Mumford et al.; U.S. Pat. No. 5,925,162Nitschke et al.; U.S. Pat. No. 6,173,587 Mumford et al.; U.S. Pat. No.6,718,798 Nitschke et al.; and U.S. Pat. No. 6,729,160 Nitschke et al.,for example.

SUMMARY

A vacuum mold shuttle system, according to the disclosure, for forming ahot glass sheet in a glass processing system includes a mold having afull downwardly facing surface that defines an initial shape to whichthe glass sheet is to be formed. The mold includes a vacuum chamberhaving a set of openings that extend from the surface of the mold intothe vacuum chamber.

The shuttle system also includes a mold support frame including at leastone connection surface for mounting the mold thereon, and at least onemold conduit operably connected at a first location to the vacuumchamber and including an opening at a second location defining a firstcoupling port. The shuttle system also includes a shuttle frameincluding a pair of generally parallel elongate beams, each of the beamsincluding at least one support surface near one end of the beam forreceiving and supporting the mold support frame thereon.

At least one vacuum source is mounted on the shuttle frame near the endof the beam opposite to the end including the mold support frame supportsurface, and a shuttle conduit operably connected at a first location tothe vacuum source. The shuttle conduit includes an opening at a secondlocation defining a second coupling port. A connector for releasablyconnecting the first coupling port to a second coupling port to providecommunication of the vacuum from the vacuum source through the shuttleconduit and through the mold conduit to the vacuum chamber of the moldfor selectively drawing a vacuum at the downwardly facing surface of themold.

According to another aspect of the disclosure, at least one guideelement may be mounted on the support surface of one of the beams forreceiving and fixing the position of the mold support frame relative tothe shuttle frame to prevent movement of the mold support frame withrespect to the shuttle frame in any direction as the mold support frameis supported thereon. At least one other guide element may be provided,which guide element is mounted on the support surface of the other oneof the beams for receiving and fixing the position of the mold supportframe relative to the shuttle frame to prevent movement of the moldsupport frame in a first direction with respect to the shuttle frame,but allow movement of the mold support frame in a second direction withrespect to this support frame as the mold support frame is supportedthereon.

According to another aspect of the disclosure, a vacuum mold shuttlesystem as described herein is provided for use in a three stage formingstation for forming a hot glass sheet, wherein the shuttle systemincludes a first upper mold having a full downwardly facing surface thatdefines an initial shape to which the glass sheet is to be formed in thefirst stage of the forming process. According to the disclosedembodiment, the three stage forming station includes an upwardly facinglower mold which receives the glass sheet from the first upper mold sothe glass sheet then sags under gravity. A downwardly facing secondupper mold of the forming station is complementary to the upwardlyfacing lower mold and cooperates with the lower mold to press form theglass sheet with curvature corresponding to the shapes of the lower moldand the second upper mold.

According to another aspect of the disclosure, the three stage formingstation also includes a conveyor from which the first upper moldreceives the glass sheet prior to the shuttle, including the first uppermold, being moved horizontally to position the glass sheet above thelower mold, which then receives the glass sheet for subsequentlyperforming the press forming with the second upper mold. This disclosedembodiment also includes a housing having a heated chamber, and has theconveyor embodied by a roll conveyor for conveying the hot glass sheetinto the heated chamber of the housing along a horizontal plane ofconveyance. The shuttle is movable horizontally within the heatedchamber to position the first upper mold between a pickup position abovethe roll conveyor and a delivery position above the lower mold which isspaced horizontally from the pickup position. In this embodiment, thevacuum source for the first upper mold may be located at the end of themold shuttle frame most distant from the heating chamber to reduceexposure of the vacuum sources to the relatively high temperaturesencountered by the first upper mold.

A gas lift jet array may be located below the plane of conveyance tosupply upwardly directed lift jets for lifting the glass sheet upwardlyfrom the roll conveyor to the first upper mold when located in itspickup position to initially form and support the glass sheet againstthe downwardly facing surface of the first upper mold. The second uppermold is spaced laterally within the heated chamber from the pickupposition of the first upper mold and is movable vertically between anupper position located above the elevation of the plane of conveyanceand a lower position closer to the elevation of the plane of conveyance,and the second upper mold has a downwardly facing surface of adownwardly convex shape that further defines the desired curvature ofthe glass sheet.

A second vacuum source may be provided to selectively draw a vacuum atthe downwardly facing surface of the second upper mold. The lower moldis located within the heated chamber below the second upper mold and isalso below the first upper mold after movement of the shuttle and firstupper mold to its delivery position with the glass sheet supportedthereon by vacuum drawn by the shuttle vacuum source. The shuttle vacuummay then be terminated to release the glass sheet onto the lower mold,and the shuttle operated to move the first upper mold back to its pickupposition.

The second upper mold is then moved downwardly from its upper positionto its lower position to cooperate with the lower mold to further pressform the glass sheet, and the second upper mold is subsequently movedupwardly to its upper position with the press formed glass sheetsupported on the second upper mold by vacuum drawn at its downwardlyfacing surface by the vacuum source associated with the second uppermold.

A delivery mold is moved to below the press formed glass sheet on thesecond upper mold in its upper position whereupon the vacuum isterminated and the glass sheet is released from the second upper moldonto the delivery mold which is then moved out of the forming stationfor delivery of the press formed glass sheet.

One or more controllers may be utilized to operate the heating chamber,the roll conveyor, the shuttle system including the first upper mold,the gas lift jet array, the second upper mold, the vacuum sources, thelower mold, and the delivery mold to perform the press forming of theglass sheet and its delivery.

While exemplary embodiments are illustrated and disclosed, suchdisclosure should not be construed to limit the claims. It isanticipated that various modifications and alternative designs may bemade without departing from the scope of the disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of an embodiment of a vacuum mold shuttlesystem according to the disclosure.

FIG. 2 is a cross-sectional end view of the mold and mold support frameof the embodiment of FIG. 1, taken along line 2-2 of FIG. 3 and viewedin the direction of the arrows.

FIG. 3 is a partial side view of the mold, mold support frame, andvacuum conduit showing the first and second coupling ports disconnectedand displaced vertically.

FIG. 4 is an isolated perspective view of the mold, mold support frame,vacuum conduit, and vacuum sources employed in the embodiment of FIG. 1.

FIG. 5 is an enlarged, perspective view of one of the coupling ports ofFIG. 4.

FIG. 6 is a partial side view of the coupling port shown in FIG. 5,showing the first and second coupling ports connected.

FIG. 7 is a partial perspective view of a support surface on one of theshuttle beams including a guide element, with the companion portion ofthe mold frame removed.

FIG. 8 is a partial perspective view of a support surface on the otherof the shuttle beams including another guide element, with the companionportion of the mold frame removed.

FIG. 9 is a schematic elevational view of a glass sheet processingsystem including a three stage forming station that may employ thedisclosed vacuum mold shuttle system for three stage forming of a hotglass sheet.

FIG. 10 is a sectional view taken through the forming station along thedirection of line 10-10 in FIG. 9 illustrating one embodiment of thethree stage forming station of the invention that includes first andsecond upper molds, a lower mold and a delivery mold for performingthree stage forming of a hot glass sheet with compound curvature.

FIGS. 11 and 12 are partial views of FIG. 10 illustrating the glasssheet processing during a cycle of operation of the system.

FIG. 13 is a flow chart that illustrates the three stage hot glass sheetforming operation of the forming station embodiment of FIGS. 10-12.

DETAILED DESCRIPTION

As required, a detailed embodiment of the present invention is disclosedherein. However, it is to be understood that the disclosed embodiment ismerely exemplary of the invention that may be embodied in various andalternative forms. The figures are not necessarily to scale. Somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for teaching one skilled in the art to practice thepresent invention.

With reference to FIGS. 1-3, the vacuum mold shuttle system for forminga hot glass sheet, generally indicated as 10, includes a mold 12 havinga full downwardly facing surface 14 that defines the initial shape towhich the glass sheet is to be formed. The mold 12 also includes avacuum chamber 16 having a set of openings 18 that extend to the surface14 from the vacuum chamber 16. A mold support frame 20 includes at leastone connection surface 22 for mounting the mold thereon, and at leastone mold conduit 24 operably connected at a first location 64 to thevacuum chamber 16. An opening defining a first coupling port 26 isprovided at a second location on the mold conduit 24.

The disclosed vacuum mold shuttle system 10 also includes a shuttleframe 28 including a pair of generally parallel elongated beams 30, 32.Each of the beams 30, 32 includes at least one support surface 34 nearone end of the beam for receiving and supporting the mold support frame20 thereon. Each of beams 30, 32 may be water-cooled to limit thethermal expansion or contraction of the beams that may result asportions of the beams are moved into and out of the heated ambient asthe mold 12 is moved within the heated ambient.

At least one vacuum source 36 may be mounted on the shuttle frame 28near the end of the beam 30 opposite the mold support frame 20. At leastone shuttle conduit 38 is operably connected at a first location to thevacuum source 36, and includes an opening at a second location defininga second coupling port 40. A connector 42 for releasably connecting thefirst coupling port 26 to the second coupling port 40 to providecommunication of the vacuum from the vacuum source 36 through theshuttle conduit 38 and the mold conduit 24 for selectively drawing avacuum (and/or creating a positive pressure) at the downwardly facingsurface 14 of the mold 12.

Referring to FIGS. 1-6, in the disclosed embodiment, the vacuum sourceis provided by positive pressure air supplied to a pair of gas jet pumps36, 37 mounted on the shuttle frame 28 at the end opposite the end wherethe mold frame 20 is located. A pair of mold conduits 24, 25 areoperably connected at one end to the vacuum chamber 16 of the mold 12(such as, for example, at locations 64, 65), and each includes anopening at the other end including a connector plate 27 defining a firstcoupling port 26. In this disclosed embodiment, each gas jet pump 36, 37is operably connected to a separate shuttle conduit 38, 39 which isshaped to extend along, and where possible, within the height profileof, the beams, 30, 32, to the end of the shuttle at which the mold 12 issupported. Each of the shuttle conduits 38, 39 include an opening at theend nearest the mold 12 including a connector plate 41 defining a secondcoupling port 40, such that when the mold 12 is installed on the shuttleframe 28 the first coupling port 26 on each of the mold conduits 24, 25aligns with the second coupling port 40 on each of the shuttle conduits38, 39. A retainer clip 42 is then slidably positioned over theconnector plates 27 and 41 to couple the conduits 38 and 24 (and 39 and25) and connect the vacuum chamber 16 of the mold 12 with the vacuumsources 36, 37.

Gas jet pumps 36, 37 may be of the type disclosed by U.S. Pat. No.4,202,681 McMaster and U.S. Pat. No. 4,222,763 McMaster so as to becapable of drawing greater and lesser extents of vacuums as well asproviding positive pressure air for providing glass sheet release duringthe forming operation as is hereinafter more fully described.

Referring to FIGS. 1, 3 and 7, in the disclosed embodiment, a firstguide element 44 is mounted on one of the support surfaces 34 of one ofthe beams 30 to receive and fix the position of the mold 12 relative tothe shuttle frame 28. The first guide element 44 may include alignmentkey 46 which is fixed to and extends upwardly from the beam supportsurface 34 (or, alternatively, projects downwardly from the mold frame20), and a complimentary receiver keyway 48 located on the mold supportframe 20 (or, alternatively, on the beam support surface 34) such that,when the mold 12 and mold support frame 20 are installed on the shuttleframe 28, alignment key 46 is received within keyway 48, therebyaligning the mold 12 in a fixed position. In the disclosed embodiment,the key 46 and keyway 48 are shaped as a “+”, such that engagement ofthe key in the keyway 48 assures that the mold frame 20 is fixed inposition relative to beam 30 at the location of the guide 44. It will beappreciated the key 46 and keyway 48 may alternatively be configured inother shapes, such as an “X”, so long as engagement of key 46 withinkeyway 48 restricts all movement of the mold frame 20 with respect tothe beam 30 at this location.

Referring to FIGS. 1 and 8, a second guide 50 may be located on theother beam 32 to register the mold frame 20 in the desired location onbeam 32. In the disclosed embodiment, the guide 50 associated with beam32 includes a second key 52 and complimentary shaped keyway which aremounted, respectively, on beam 32 and mold frame 20 (or vice versa) tofix the positioning mold frame 20 along one axis (such as the length) ofthe beam 32, but allow for movement of mold frame 20 along another axis(such as the width) of the beam 32. In the disclosed embodiment, thesecond key 52 is shaped as a “−”, and the corresponding keyway is a slotwhich is suitably sized to accept the key 52 therein and preventmovement of the mold frame 20 with respect to beam 32 in one direction(such as, for example, along the length of the shuttle frame), but allowthe key to slide in another direction (such as, for example, transverseto the length of the shuttle frame).

By utilizing the first guide 44 and second guide 50 in these describedshapes, the mold 12 and mold frame 20 are aligned at a fixed position inone direction (e.g., along the length) on the shuttle support beams 30,32. In addition, mold frame 20 is fixed in position in all directions atfirst guide 44 with respect to beam 30, but mold frame 20 is allowed tomove with respect to beam 32 in a direction transverse to the length ofbeam 32 at second guide 50. This arrangement thus aligns the mold at afixed point on the shuttle frame 28 at guide 44, but allows for, forexample, any thermal expansion or contraction that may result as themold 12 and frame 20 are moved into and out of the heated ambient byallowing the mold frame 20 (and mold 12) to move with respect to theshuttle beam 32 in a selected direction (e.g., transverse to the lengthof beam 32) at guide 50.

Referring now to FIGS. 9 and 10, the disclosed vacuum mold shuttlesystem may be employed in a glass sheet forming system generallyindicated by 200 which includes a furnace 202 having a heating chamber204 for providing a heated ambient for heating glass sheets. A conveyor206 of the system conveys the heated glass sheet in a generallyhorizontally extending orientation and is preferably of the rollconveyor type including rolls 208 like those disclosed by U.S. Pat. No.3,806,312 McMaster; U.S. Pat. No. 3,934,970 McMaster et al., U.S. Pat.No. 3,947,242 McMaster et al.; and U.S. Pat. No. 3,994,711 McMaster etal. A three stage forming station 210 of the system 200 is constructedaccording to the present disclosure and performs the method thereof suchthat both the forming station and the forming method are described in anintegrated manner to facilitate an understanding of different aspects ofthe disclosure. The forming station 210 has a construction with pressforming somewhat similar to that of the disclosure of the aforementionedU.S. Pat. No. 4,661,141 and the other United States patents set forth inthe above Background section of this application. Furthermore, theforming station 210 has an insulated housing 212 defining a heatedchamber 214 in which forming apparatus 216 of the forming station islocated as best shown in FIG. 10.

As illustrated in FIGS. 10-12, the glass sheet forming apparatus 216 mayemploy the disclosed vacuum mold shuttle system 10′, including a firstupper mold 12′ that picks up the softened glass sheet from the heaterconveyor 206 during a first stage of the hot glass sheet forming, thenmoves the glass sheet horizontally to a delivery position shown in FIG.11 where a lower mold 222 is located, and releases the glass sheet Gonto the lower mold 222 for gravity sagging. As such, there is arelatively limited time for gravity sagging so that the shape can bemore accurately controlled.

After the glass sheet is deposited on the lower mold 222 by the firstupper mold 12′, the first upper mold 12′ moves back from its deliveryposition of FIG. 11 to its pickup position of FIG. 10 and the secondupper mold 220 moves downwardly as shown in FIG. 12 to cooperate withthe lower mold 222 in press forming the glass sheet. Some vacuum formingof the glass on the facing surface 270 of the second upper mold 220 mayalso be accomplished if desired. After press forming, the second uppermold 220 moves upwardly with the glass sheet supported against itsdownwardly facing surface 270 by a drawn vacuum and the delivery mold224 shown in FIG. 10 is moved from a post-forming station (such as, forexample, the quench station 226) into the forming station 210 to receivethe formed glass sheet for movement out of the forming station 210 (suchas to the quench station 226 of the disclosed embodiment) for furtherprocessing.

As shown in FIG. 10, in this disclosed embodiment the first upper mold12′ has a support frame 20′ that is supported by a shuttle frame 28′including elongated beams 30′, 32′ (only one shown) that are moved by anactuator 242 through a connection 244. These beams 30′, 32′ aresupported at one end by one or more associated rollers 246 that aremounted by one or more actuators 248. The other ends of the beams 30′,32′ may be supported by a carriage 260 (best shown in FIG. 1) which mayinclude a vertical lift mechanism 262 powered by an actuator 249 (seeFIG. 1). In this embodiment, rollers 246, lift mechanism 262 and theirassociated actuators 248 and 249 may be controlled to provide verticalmovement of the beams (and hence vertical movement of the first uppermold 12′) during its operation. More specifically, the first upper mold12′ can be moved downwardly to about one half inch (12 to 15 mm) fromthe conveyor 206 for the initial pickup of the glass sheet and can thenbe moved upwardly so as to move above covers 250 located above the endsof the conveyor rolls 208. Lateral rollers 252 also contact one of thebeams 30′ to provide lateral positioning during movement of the firstupper mold 12′ between its pickup position shown in FIG. 10 and itsdelivery position shown in FIG. 11. It should be appreciated that oneembodiment of the shuttle positioning system including rollers 246 and252 is disclosed in U.S. Patent Application Ser. No. 62/249,697, thedisclosure of which is incorporated herein in its entirety.

Station 210, illustrated in FIGS. 10-12, thus has three stages ofoperation wherein the glass sheet may be formed on the first upper mold12′ with curvature in a first direction and straight line elements in asecond direction transverse to the first direction, by gravity on thelower mold 222 after receipt thereby from the first upper mold 12′ inits delivery position shown in FIG. 11, and finally by the press formingbetween the second upper mold 220 and the lower mold 222 and/or vacuumforming on the second upper mold 220 as shown in FIG. 12. It will beappreciated that the disclosed vacuum mold shuttle system 10 may beemployed in other multi-stage forming systems, such as other embodimentsof three stage forming systems, which forming systems may includeadditional details as are disclosed in U.S. Pat. No. 9,452,948 B2,entitled “Three Stage Forming Station And Method For Forming A Hot GlassSheet With Transverse Curvature”, the disclosure of which isincorporated herein in its entirety.

Referring again to FIG. 10, the lower mold 222 as illustrated may besupported by a framework 254 that is supported by actuators 256, such asscrew jacks, for vertical movement. This vertical movement can bedownward to allow the first upper mold 12′ to move over the lower mold222 and then upward so that the release of the glass sheet is at a moreclosely spaced relationship to control positioning. In addition, thevertical movement of the lower mold 222 can also be used in cooperationwith the vertical movement of the second upper mold 220 to perform thepress bending.

A gas lift jet array 258 may be included in the forming station asillustrated in FIG. 10. The gas lift jet array 258 is located below theplane of conveyance C of the hot glass sheet and includes gas jet pumpsthat supply upwardly directed gas jets for lifting the glass sheet Gupwardly from the roll conveyor 206 to initially form and support theglass sheet against the downwardly facing surface 14′ of the first uppermold 12′ which is then positioned above the lower mold as previouslydescribed with the glass sheet supported against its downwardly facingsurface as shown in FIG. 11. The gas jet pumps may of the type disclosedby U.S. Pat. No. 4,204,854 McMaster et al. and U.S. Pat. No. 4,356,018McMaster et al. such that a primary gas flow therefrom induces asecondary gas flow many times the extent of the primary gas flow inorder to provide the lifting. A downwardly facing surface 14′ of thefirst upper mold 12′ also has an array of vacuum holes 18′ through whicha vacuum may be drawn to also provide initial lifting of the glass sheetand to then support the glass sheet as is herein described. The releaseof the glass sheet can be provided by the termination of the vacuumdrawn and the termination of the upwardly directed gas jets provided bythe gas jet array 258 previously described, as well as by providingpositive pressure gas to the mold surface 14′.

It should be appreciated that one embodiment of the gas jet lift array258 is disclosed in co-pending U.S. patent application Ser. No.14/929,799, entitled “Lift Device For A Glass Processing System”, thedisclosure of which is incorporated herein in its entirety.

The system 200 may further include a controller or control unit 88,shown in FIG. 9, for controlling operation of the above components. Thecontrol unit 88 may have a bundle of connections 90 for connecting withthe various components of the system 200, such as the vacuum sources 36,37 and the vacuum mold shuttle system actuators 242, 248, and 249 forthe first upper mold 12′, the heater 204, the roller conveyor system206, the second upper mold 220, the lower mold 222, the delivery mold224, and the quench station 226. Furthermore, the control unit 88 mayinclude any suitable hardware and/or software for controlling operationof the above components in order to perform the press forming of theglass sheet G, as well as its delivery and quenching (e.g., forperforming the particular algorithms represented by the functionsdescribed herein). For example, the control unit 88 may include one ormore processors in communication with one or more storage devices ormemory units, which include computer readable program instructions thatare executable by the one or more processors so that the control unit 88may control operation of the vacuum mold shuttle 10, as well as theother above-described components of the glass sheet forming system. Thecontrol unit 88 may also, or instead, include one or more applicationspecific integrated circuits, programmable gate arrays, programmablelogic devices, and/or digital signal processors. In lieu of theconnections 90, the control unit 88 may instead be connected wirelesslyto one or more of the above components. Furthermore, the control unit ofthe vacuum mold shuttle system 10 may be part of the control unit 88, orit may be separate from the control unit 88 but configured tocommunicate with the control unit 88.

During development of the forming station 210, the inventors havedetermined that glass sheet forming with compound curvature (i.e.,curvature about multiple, non-parallel axes) upon initial forming on anupper mold can cause buckling at the central viewing area of the glasssheet due to excess glass at the glass sheet periphery when the flatglass sheet assumes the curvature in crossing directions with nostraight line elements, and such buckling results in distorted optics asto transmission and/or reflection in the central viewing area of theglass. It has also been determined that use of a first upper mold withstraight line elements during the initial stage of forming, thenallowing the gravity sag forming on the lower mold to begin curvatureabout other axes (e.g., axes transverse to the axes of curvature of thefirst upper mold), and subsequently performing the final press formingof the glass sheet reduces optical distortions both as to transmissionand reflection in the central view area of the formed glass sheet. Forpurposes of this application, the term “straight line elements” meansstraight lines between two opposite extremities of the first upper moldsurface 14′ and of the glass sheet after the first stage of forming,which straight lines have midpoints from which the mold surface andinitially formed glass sheet are displaced no more than about 0.5%, andpreferably no more than about 0.3%, of the distance between theextremities.

With reference to the flow chart of FIG. 13, the embodiment of FIGS.10-12 performs the press forming operation beginning, at 300, by theheating of the glass sheet G in the furnace and its subsequentconveyance 302 into the forming station, followed by the first uppermold receiving the glass sheet from the conveyance for initial formingin the first stage, at 304, and then the horizontal movement 306 of thefirst upper mold and the glass sheet to above the lower mold. Then, theglass sheet release 308 from the first upper mold onto the lower moldprovides gravity sagging in the second stage, and the second upper moldis moved downwardly at 310 to the lower mold for press and/or vacuumforming with compound curvature (including curvature about an axis oraxes transverse to the axes of curvature of the first upper mold) in thethird stage. The second upper mold and glass sheet are then movedupwardly at 312 followed by the delivery mold movement 314 below thesecond upper mold to receive the formed glass sheet and then move it outof the forming station for delivery to a post-forming processingstation.

The disclosed embodiment of FIGS. 10-12 can have reduced cycle time bythe vertical positioning of the constructions disclosed. In thisdisclosed embodiment, the vertical positioning permits both the firstupper mold 12′ and the delivery mold 224 to be below the second uppermold 220 at the same time so successive cycles overlap to reduce cycletime.

All of the previously mentioned patents are assigned to the applicant ofthe present application and are hereby incorporated by reference.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. A vacuum mold shuttle system for forming a glasssheet comprising: a mold including a downwardly facing surface thatdefines a shape to which the glass sheet is to be initially formed, avacuum chamber, and openings that extend from the downwardly facingsurface to the vacuum chamber; a mold support frame including at leastone connection surface for mounting the mold thereon, and a mold conduitoperably connected at a first location to the vacuum chamber andincluding an opening at a second location defining a first couplingport; a shuttle frame including a pair of generally parallel elongatebeams, each of the generally parallel elongate beams including a supportsurface near one end for receiving and supporting the mold support framethereon; a vacuum source mounted on the shuttle frame near an end of oneof the generally parallel elongate beams opposite the end including thesupport surface; a shuttle conduit operably connected at a firstlocation to the vacuum source and including an opening at a secondlocation defining a second coupling port; and a connector for releasablyconnecting the first coupling port to the second coupling port toprovide communication of a vacuum from the vacuum source through theshuttle conduit and through the mold conduit to the vacuum chamber forselectively drawing a vacuum at the downwardly facing surface of themold.
 2. The vacuum mold shuttle system as in claim 1 including at leastone guide element associated with one of the generally parallel elongatebeams for fixing position of the mold support frame relative to theshuttle frame to prevent movement of the mold support frame with respectto the shuttle frame in any direction as the mold support frame issupported thereon, and at least one other guide element associated withthe other one of the generally parallel elongate beams for fixing theposition of the mold support frame relative to the shuttle frame toprevent movement of the mold support frame in a first direction withrespect to the shuttle frame, but allow movement of the mold supportframe in a second direction with respect to the shuttle frame as themold support frame is supported thereon.
 3. The vacuum mold shuttlesystem as in claim 2 wherein each of the at least one guide element andeach of the at least one other guide element include a registrationsurface which is fixed to and projects outwardly from a plane of thesupport surface of one of the generally parallel elongate beams or asurface of the mold support frame, and a complementary-shapedregistration surface which is fixed to and recessed inward from theplane of the support surface of the one of the generally parallelelongate beams or the surface of the mold support frame such that eachoutwardly projecting registration surface engages a complementary-shapedregistration surface to prevent movement of the mold support frame withrespect to the shuttle frame in at least one direction.
 4. The vacuummold shuttle system as in claim 1 wherein the vacuum source includes atleast one vacuum generator.
 5. The vacuum mold shuttle system as inclaim 1 wherein the generally parallel elongate beams are water-cooled.6. The vacuum mold shuttle system as in claim 1 wherein the downwardlyfacing surface of the mold has curvature in a first direction andstraight line elements in a second direction transverse to the firstdirection for forming the glass sheet with curvature in the firstdirection while maintaining straight line elements in the seconddirection.
 7. A three stage forming station for forming a glass sheetwith compound curvature, the three stage forming station comprising thevacuum mold shuttle system of claim 1, wherein the mold is a first uppermold and the downwardly facing surface is a first upper mold surfacehaving curvature in a first direction and straight line elements in asecond direction transverse to the first direction for initially formingthe glass sheet with curvature in the first direction while maintainingstraight line elements in the second direction, and wherein the threestage forming station further comprises: an upwardly facing lower mold,that has curvature at least in the first direction and permits glasssheet curvature in the second direction, for receiving the glass sheetfrom the first upper mold so the glass sheet is able to sag undergravity along the second direction to have some curvature in the seconddirection as well as curvature in the first direction; and a downwardlyfacing second upper mold, that has compound curvature and iscomplementary to the upwardly facing lower mold, for cooperating withthe upwardly facing lower mold to form the glass sheet with compoundcurvature corresponding to the shapes of the upwardly facing lower moldand the downwardly facing second upper mold.
 8. The three stage formingstation of claim 7 further comprising a conveyor from which the firstupper mold may receive the glass sheet prior to the first upper moldwith the glass sheet being moved laterally to above the upwardly facinglower mold which is configured to receive the glass sheet for pressforming between the upwardly facing lower mold and the downwardly facingsecond upper mold.
 9. The three stage forming station of claim 8 furthercomprising: a housing having a heated chamber; the conveyor beingembodied by a roll conveyor for conveying the glass sheet into theheated chamber of the housing along a horizontal plane of conveyance;the shuttle frame being movable horizontally to selectively position thefirst upper mold within the heated chamber between a pickup positionabove the roll conveyor and a delivery position spaced horizontally fromthe pickup position; a gas lift jet array located below the horizontalplane of conveyance to supply upwardly directed lift jets for liftingthe glass sheet upwardly from the roll conveyor to the first upper moldwhen located in its pickup position to initially form and support theglass sheet against the downwardly facing surface of the first uppermold; the downwardly facing second upper mold being spaced horizontallywithin the heated chamber from the pickup position of the first uppermold and being movable vertically between an upper position locatedabove an elevation of the horizontal plane of conveyance and a lowerposition closer to the elevation of the horizontal plane of conveyance,and the downwardly facing second upper mold having a downwardly facingsurface of a downwardly convex shape that defines its transversecurvature; an additional vacuum source for selectively drawing a vacuumat the downwardly facing surface of the downwardly facing second uppermold; the upwardly facing lower mold being located within the heatedchamber below the downwardly facing second upper mold, and alsoconfigured to be positioned below the first upper mold after movement ofthe first upper mold to its delivery position with the glass sheetsupported thereon by vacuum drawn by the vacuum source whereupon thevacuum drawn by the vacuum source is terminatable to release the glasssheet onto the upwardly facing lower mold and the first upper mold ismovable back to its pickup position; the downwardly facing second uppermold then being movable downwardly from its upper position to its lowerposition to cooperate with the upwardly facing lower mold to press formthe glass sheet with curvature in transverse directions, and thedownwardly facing second upper mold is subsequently movable upwardly toits upper position with the glass sheet supported on the downwardlyfacing second upper mold by vacuum drawn at its downwardly facingsurface by the additional vacuum source; a delivery mold that is movableto a position below the downwardly facing second upper mold when thedownwardly facing second upper mold is in its upper position with theglass sheet on the downwardly facing second upper mold, whereupon thevacuum from the additional vacuum source is terminatable to release theglass sheet from the downwardly facing second upper mold onto thedelivery mold which is then movable away from the position below thedownwardly facing second upper mold for delivery of the glass sheet; anda controller configured to operate the roll conveyor, the first uppermold, the gas lift jet array, the downwardly facing second upper mold,the vacuum source on the shuttle frame, the additional vacuum source forthe downwardly facing second upper mold, the upwardly facing lower mold,and the delivery mold to perform the press forming of the glass sheetand its delivery.
 10. The three stage forming station of claim 9 whereinthe vacuum source is configured to be operated by the controller toprovide vacuum to the downwardly facing surface of the first upper moldto cooperate with the gas lift jet array in lifting the glass sheet fromthe roll conveyor into contact with the downwardly facing surface of thefirst upper mold for initial forming and support of the glass sheet. 11.The three stage forming station of claim 10 wherein, after the glasssheet is moved upwardly and contacts the downwardly facing surface ofthe first upper mold, the controller is configured to terminateoperation of the gas lift jet array while continuing to operate thevacuum source to provide the vacuum that is then sole support of theglass sheet on the first upper mold.
 12. The three stage forming stationas in claim 9 further including a quench station to which the deliverymold is movable to move the glass sheet for quenching.
 13. The threestage forming station of claim 7 wherein the upwardly facing lower moldhas a ring shape configured to support the glass sheet as it sags bygravity.
 14. A three stage forming station for forming a hot glass sheetwith transverse curvature, the three stage forming station comprising: adownwardly facing first upper mold having a downwardly facing surface, avacuum chamber and openings that extend from the vacuum chamber to thedownwardly facing surface, wherein the downwardly facing surface hascurvature in a first direction and straight line elements in a seconddirection transverse to the first direction, for initially forming thehot glass sheet with curvature in the first direction while maintainingstraight line elements in the second direction; a mold support frameincluding at least one connection surface for mounting the downwardlyfacing first upper mold thereon, a mold conduit operably connected at afirst location to the vacuum chamber and including an opening at asecond location defining a first coupling port; a shuttle frameincluding a pair of generally parallel elongate beams, each of thegenerally parallel elongate beams including a support surface near oneend for receiving and supporting the mold support frame thereon; avacuum source mounted on the shuttle frame near an end of one of thegenerally parallel elongate beams opposite the end including the supportsurface; a shuttle conduit operably connected at a first location to thevacuum source and including an opening at a second location defining asecond coupling port; a connector for releasably connecting the firstcoupling port to the second coupling port to provide communication of avacuum from the vacuum source through the shuttle conduit and throughthe mold conduit to the vacuum chamber for selectively drawing a vacuumat the downwardly facing surface of the downwardly facing first uppermold; an upwardly facing lower mold, that has curvature in at least thefirst direction and permits glass sheet curvature in the seconddirection, for receiving the hot glass sheet from the downwardly facingfirst upper mold so the hot glass sheet is able to sag under gravityalong the second direction to have some curvature in the seconddirection as well as curvature in the first direction; a downwardlyfacing second upper mold, that has compound curvature and iscomplementary to the upwardly facing lower mold, for cooperating withthe upwardly facing lower mold to press form the hot glass sheet withcompound curvature corresponding to the shapes of the upwardly facinglower mold and the downwardly facing second upper mold; and a deliverymold for receiving the hot glass sheet from the downwardly facing secondupper mold for delivery to a post-forming processing station.
 15. Thethree stage forming station of claim 14 wherein the downwardly facingsurface of the downwardly facing first upper mold has a downwardlyconvex shape, and the downwardly facing second upper mold has adownwardly facing surface of a downwardly convex shape.
 16. The threestage forming station of claim 15 wherein the downwardly facing surfaceof the downwardly facing second upper mold includes an associated arrayof vacuum holes.
 17. The three stage forming station of claim 15 whereinthe upwardly facing lower mold has an upwardly concave shape.
 18. Thethree stage forming station of claim 17 wherein the upwardly facinglower mold has a ring shape that defines its upwardly concave shape andis configured to support the hot glass sheet as it sags by gravity. 19.The three stage forming station of claim 14 wherein the downwardlyfacing surface of the downwardly facing first upper mold has adownwardly convex shape, the downwardly facing second upper mold has adownwardly facing surface of a downwardly convex shape including anassociated array of vacuum holes, and the upwardly facing lower mold hasa ring shape that defines an upwardly concave shape and is configured tosupport the hot glass sheet as it sags by gravity.
 20. The three stageforming station of claim 14 wherein the upwardly facing lower mold has aring shape of an upwardly concave shape that has curvature in at leastthe first direction and permits glass sheet curvature in the seconddirection; and the downwardly facing second upper mold has a downwardlyconvex shape with an array of vacuum holes.